/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.hdfs.server.namenode;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.util.Enumeration;
import java.util.List;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSInputStream;
import org.apache.hadoop.hdfs.DFSClient;
import org.apache.hadoop.hdfs.DFSInputStream;
import org.apache.hadoop.hdfs.server.common.JspHelper;
import org.apache.hadoop.hdfs.server.datanode.DataNode;
import org.apache.hadoop.hdfs.server.datanode.DatanodeJspHelper;
import org.apache.hadoop.io.IOUtils;
import org.apache.hadoop.security.UserGroupInformation;
import org.apache.hadoop.util.ServletUtil;
import org.mortbay.jetty.InclusiveByteRange;
@InterfaceAudience.Private
public class StreamFile extends DfsServlet {
/** for java.io.Serializable */
private static final long serialVersionUID = 1L;
public static final String CONTENT_LENGTH = "Content-Length";
/* Return a DFS client to use to make the given HTTP request */
protected DFSClient getDFSClient(HttpServletRequest request)
throws IOException, InterruptedException {
final Configuration conf =
(Configuration) getServletContext().getAttribute(JspHelper.CURRENT_CONF);
UserGroupInformation ugi = getUGI(request, conf);
final ServletContext context = getServletContext();
final DataNode datanode = (DataNode) context.getAttribute("datanode");
return DatanodeJspHelper.getDFSClient(request, datanode, conf, ugi);
}
@SuppressWarnings("unchecked")
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
final String path = ServletUtil.getDecodedPath(request, "/streamFile");
final String rawPath = ServletUtil.getRawPath(request, "/streamFile");
final String filename = JspHelper.validatePath(path);
final String rawFilename = JspHelper.validatePath(rawPath);
if (filename == null) {
response.setContentType("text/plain");
PrintWriter out = response.getWriter();
out.print("Invalid input");
return;
}
Enumeration<String> reqRanges = request.getHeaders("Range");
if (reqRanges != null && !reqRanges.hasMoreElements()) {
reqRanges = null;
}
DFSClient dfs;
try {
dfs = getDFSClient(request);
} catch (InterruptedException e) {
response.sendError(400, e.getMessage());
return;
}
DFSInputStream in = null;
OutputStream out = null;
try {
in = dfs.open(filename);
out = response.getOutputStream();
final long fileLen = in.getFileLength();
if (reqRanges != null) {
List<InclusiveByteRange> ranges =
InclusiveByteRange.satisfiableRanges(reqRanges, fileLen);
StreamFile.sendPartialData(in, out, response, fileLen, ranges);
} else {
// No ranges, so send entire file
response.setHeader("Content-Disposition", "attachment; filename=\"" +
rawFilename + "\"");
response.setContentType("application/octet-stream");
response.setHeader(CONTENT_LENGTH, "" + fileLen);
StreamFile.copyFromOffset(in, out, 0L, fileLen);
}
in.close();
in = null;
out.close();
out = null;
dfs.close();
dfs = null;
} catch (IOException ioe) {
if (LOG.isDebugEnabled()) {
LOG.debug("response.isCommitted()=" + response.isCommitted(), ioe);
}
throw ioe;
} finally {
IOUtils.cleanup(LOG, in);
IOUtils.cleanup(LOG, out);
IOUtils.cleanup(LOG, dfs);
}
}
/**
* Send a partial content response with the given range. If there are
* no satisfiable ranges, or if multiple ranges are requested, which
* is unsupported, respond with range not satisfiable.
*
* @param in stream to read from
* @param out stream to write to
* @param response http response to use
* @param contentLength for the response header
* @param ranges to write to respond with
* @throws IOException on error sending the response
*/
static void sendPartialData(FSInputStream in,
OutputStream out,
HttpServletResponse response,
long contentLength,
List<InclusiveByteRange> ranges)
throws IOException {
if (ranges == null || ranges.size() != 1) {
response.setContentLength(0);
response.setStatus(HttpServletResponse.SC_REQUESTED_RANGE_NOT_SATISFIABLE);
response.setHeader("Content-Range",
InclusiveByteRange.to416HeaderRangeString(contentLength));
} else {
InclusiveByteRange singleSatisfiableRange = ranges.get(0);
long singleLength = singleSatisfiableRange.getSize(contentLength);
response.setStatus(HttpServletResponse.SC_PARTIAL_CONTENT);
response.setHeader("Content-Range",
singleSatisfiableRange.toHeaderRangeString(contentLength));
copyFromOffset(in, out,
singleSatisfiableRange.getFirst(contentLength),
singleLength);
}
}
/* Copy count bytes at the given offset from one stream to another */
static void copyFromOffset(FSInputStream in, OutputStream out, long offset,
long count) throws IOException {
in.seek(offset);
IOUtils.copyBytes(in, out, count, false);
}
}